Autonomous vehicles use various computing systems to aid in the transport of passengers from one location to another. Some autonomous vehicles may require an initial input or continuous input from an operator, such as a pilot, driver, or passenger. Other autonomous systems, for example autopilot systems, may be used only when the system has been engaged, which permits the operator to switch from a manual mode (where the operator exercises a high degree of control over the movement of the vehicle) to an autonomous mode (where the vehicle essentially drives itself) to modes that lie somewhere in between.
Such vehicles are typically equipped with various types of sensors in order to detect objects in the surroundings. For example, autonomous vehicles may include lasers, sonar, radar, cameras, and other devices which scan and record data from the vehicle's surroundings. Sensor data from one or more of these devices may be used to detect objects and their respective characteristics (position, shape, heading, speed, etc.). This detection and identification is a critical function for the safe operation of autonomous vehicle.
For example, some autonomous vehicles may use sensors to detect objects and adjust speed accordingly. For example, an autonomous vehicle may automatically (in other words, without input from a driver) slow its speed down if vehicles traveling in an adjacent lane are traveling slowly. This may mimic the behavior of a typical driver in a high-occupancy vehicle (“HOV”) lane on a highway who slows his or her vehicle down when traffic in the adjacent lane is moving much slower. For example, this type of maneuver may prevent accidents when a slow moving vehicle moves into the HOV lane.
Other semi-autonomous systems using similar speed control to prevent accidents. For example, adaptive cruise control systems in a typical vehicle may allow a driver to input a maximum speed of the vehicle. If the adaptive cruise control system detects an object in the lane directly in front of the vehicle, the adaptive cruise control may slow the vehicle down to maintain a specified distance from the object. If the object speeds up or is no longer directly in front of the vehicle, the adaptive cruise control system may increase the speed of the vehicle back to the speed input by the driver.